Biological Molecules- Carbohydrates 1.1

Disaccharides- Sugar made up of 2 monosacaride units joined by a glycosidic bond, formed in a condensation reaction e.g

Sucrose,- stored in plants - made from A Glucose + Fructose

Lactose, - in milk - made from AGlucose + B Glucose

Maltose- found in germinating seeds e.g barley - made from A Glucose + A Glucose

ALL D are made through a Condensation Reaction between the 2 molecules creating a Glycosidic Bond.

Condensation Reaction- Molecule of H20 is removed from the reacting molecules and a bond is formed between them

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Carbohydrates 1.1

Polysaccharides- Polymer made up of long chains of monosaccharide units joined ny glycosidic bonds (molecules containing 11 or more monosaccharides) e.g Glycogen, Starch formed from amylopectin, amylose

Bonds which hold 3D shapes of proteins together are affected by condtion changes e.g temp/Ph. Result in bonds breaking, loss 3D shape = denatured. Can cause proteins such as enzymes- stop working efficently.

M contribtes to Growth- PLANTS= increase cell number and size. MAMMALS= Continous growth INSECTS- Discontinous- shed exoskeleton while new = soft = expand by taking in air/water. when new skeleton hardened air and water = released = room for tissues increase in size.

SPECIES- Group of closely related organisms are potentially capable of interbreeding to produce fertile offspring

MORPHOLOGICAL SPECIES CONCEPT- Based apperance of organsims, easy identify organisms, sexual dimorphism = confusing when male and females look different

REPRODUCTIVE SPECIES CONCEPT- Based interbreeding to produce fertile offspring, overcomes sexual dimorphism, some org = not same species produce fertile offspring e.g tiger/lion not always right

DNA BARCODING- Use short section DNA from standarised region of geonome all animals. Gene region = effective identifying animal groups- short enough = sequenced quickly but still identify various species

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Biochemical Relationships 3.1

GEL ELECTROPHORESIS- Movement of small particles through gel application of electricity.

BIOCHEMICAL RELATIONSHIPS- scientists analyse structure of different chemicals organsims to identity relationships between them = molecular phylogeny. African, American porcupines look similar but biochemical analysis implies they are distantly related. By analysing sequence of amino acids in proteins = see relationships within group e.g phylum

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Natural Selection 3.2

EVOLUTION- Change in genetic compostion of population of organsims over several generations as a result of natural selection acting upon variation

organisms reproduce sexually = variation

organsims produce offspring in excess

organisms that inherit advantageous characteristics most likely to surive pass on advantagous characteristic to offspring

org inherit charcteristics put them at disadvantage = more likely to die out before reproduce

Neo- Darwinism- Developed due to growth = human knowledge of genetics presenting more modern way evo

Change in Genotype -> change in phenotype -> advantageous alleles

Niches- role of an organism in its community e.g food niche

industral melanism- evolution of dark coulored individuals in a habitat thats been made darker or lighter by industrial pollution (antipollution leg 1960s)

directional selction- change from dominant phenotype to another in response to change in environment